Abstract: The present disclosure provides a method for evaluating a likelihood that a subject belongs to a group for a classification attribute having a binary classification. The method includes: receiving a subject score for an observation value of the subject; acquiring sensitivity and specificity of the subject score with the subject score as a parameter, by using a relational expression established between the sensitivity and the specificity with a score for the observation value as a parameter; acquiring a prior probability of an attribute of the subject; and acquiring a likelihood of belonging to a classification attribute specific to the subject based on the sensitivity, the specificity, and the prior probability of the subject.